geosphere as background

[leo_surrealismo]

hi, Can someone explain me how to setup a scene with a geosphere acting as a background and not to interfere with ilumination?
thank you!

leo

[TomG]

Why would you want to, compared to using the overrides (Direct Visibility, Reflection, Refraction etc.)?

[TomG]

(if you do have a particular reason - but it should be a good one ;) - just using a CoronaLight material with Emit Light turned off, and set the geo not to cast or receive shadows should do the trick)

[leo_surrealismo]

because I am using it on a 360 tour and I need to fake the movement within the boundaries.
I did what you told me, but it is still casting a weird shadow.

[TomG]

Best thing is to post an image showing what you mean by a weird shadow :)

[leo_surrealismo]

take a look at the images and see the weird shadow :)

[maru]

That's a known issue listed under "black highlights" here - https://support.chaos.com/hc/en-us/articles/4528311915025-Known-bugs-and-limitations


I am attaching images showing it, and a workaround.
The workaround is to split the background material into two separate Light Materials:
- material A with "emit" off
- material B with "emit" on and "occlude" off
- then plug material A into all slots of a rayswitch material
- then plug material B into "reflect override" slot of the same rayswitch material
- then apply the rayswitch material to your background object

Let me know if you need further help / explanation here.

[leo_surrealismo]

thank you! it´s working now on my scene!
have a nice day!

[leo_surrealismo]

I have noticed something,  I need this background to affect visible reflections... in this setup, I can not see how to do this.

[maru]

The material that you have plugged into "reflection override" should be affecting reflections. It doesn't seem to work like this?

[leo_surrealismo]

no, It does not.  Should I upload a scene to you?

[maru]

If you have a minimal scene, that would be great. If you prefer to send some production scene, you can PM me or upload it here: https://corona-renderer.com/upload

[leo_surrealismo]

many thanks maru.
pm sent.

[leo_surrealismo]

hi again,
could you spot what is the problem here on my setup?
I am in another project and the problem came back again. 
I have a geosphere with a rayswitch material just as corona support told me (emit off  on refract and direct override; emit On on reflect override). But when I do this, it starts reflecting my CoronaSky.  and If I unthick emit light, the reflection with glossiness of 1 are perfect, but I get black speculars.

thanks!

[PROH]

You need to put the "emit off" material into the GI slot in the Ray Switch material.